Lining for pebble or ball mills.



H. A. HANSEN & J. IVI. SCHMUESER. LINING FOR PEBBLE 0R BALL MILLS.

APPLICATION FILED IuLY 21, I9Is.

1,153,844. PatentedSept. 14, 1915.

2 `SHEETS-SHED l.

@lfm/Immo@ @14mm/Cow H- A. HANSEN & l. Nl. SCHMUESER. LINING Foa PEBBLE 0R BALL Mms. APPLICATION F|LED JULY 21| 1913. Ljl., PaytentedSept. 14, 1915.

2 SHEETS-SHEET 2.

HANS A. HANSEN AND JOSEPH M. SCHMUESER, 0F SMUGGLER, COLORADO.

LINING FOR PEBBLE OR BALL MILLS.

To all whom it may concern Be it known that we, 'HANS and JOSEPH M. SoHMUEsER, citizens nof the United States, residing at Smuggler, county of San Miguel, and State of Colorado, have invented certain new and useful Improvements in Linings for Pebble or Ball Mills; and we do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and lfigures of reference marked thereon, which form a part of this specification.

Our invention relates to improvements in linings for ball or pebble mills and may be said to be an improvement over the construction shown in a previous application Serial No. 745,561, filed by us on Februaryl 1, 1913.

One of the objects of the invention is to provide ribs upon the lining units, said ribs being of such form as to prevent any great amount of slippage of the balls or pebbles -upon the lining and yet at the same time not to be open to the objection of carrying the balls or pebbles high enough in the mill to fall against the lining on the opposite side to the possible damage of the latter.

A further object is to lessen the power required to rotate the mill which results from not raising the balls so high, or differently stated, permitting faster rotation of the mill and quicker grinding with the same eX- penditure of power. I

Other objects will appear hereinafter as we proceed with the description of that embodiment of the invention which for the purposes of the present application, we have illustrated in the accompanying drawings.`

In this drawing-Figure 1 is a central longitudinal sectional viewV of a mill provided with our improved lining. Fig. 2 is a view in detail of one of the units of our lining. Fig. 3 is a similar view of another unit. Fig. 4 is a similar view of still another unit. Fig. 5 is a cross section taken upon the line 5 5, Fig. 1 looking in the direction of the arrow. Fig. 6 is a plan viewin detail of the door lining. Fig. 7 is a plan view in detail of the two units in which the door opening'is located. Fig. 8 is a detail plan view of the different units of a modified form of lining. Fig. 9 illustrates a modified form of lining for the longer conoidal part A. HANSENv Specication of Letters Patent. Patented Sept, 14, 1915 Application iled July 21, 1913. Serial No. 780,242. v

or section of the mill. Fig. 10 shows the cross sections of a number of units of modified form. Fig. 11 is a view similar to Fig. 9, disclosing means for holding the ,lining in place.

Similar reference characters refer to like parts throughout the views.

In the drawings, which fornra p-art of this specication, the numerals 5, 6 and 7 refer to the two conoidal and the cylindrical parts respectively of the casing of a pebble or ball mill. Thecasing is supported upon and secured to hollow trunnions 8 and 'a which have collars 10 and 11 fixed thereupon to coperate withJ the journals (not shown) for preventing longitudinal movement thereof.

The casing is provided with a number of strips or rows of belting 12 preferably in short pieces upon the inside, said rows running completely around the casing. The spaces between the belting 12 are filled with cement 13, the thickness of the cement layer being the same as that of the belting. A hollow end support 14 is next inserted within the.-trunnion 9, the shoulder 15 in said support abutting against the shoulder 16 upon the trunnion, thus preventing the support from beinO' moved outwardly. The support 14 has a dat wall 17 which acts as an abutment for the outer extremities of the lining units 18. These units are made concaVo-conveX, their outer surfaces being of a curvature similar to that of the casing against which they rest. The side edges 19 of these units are inclined toward the middle in planes which if extended would include the aXis of the mill.

Two of the units, namely 18a .and 18b have their adjacent edges beveled olf inwardly and away from each other as at 20 and 21 (see Fig. 5). When the other units have been set in place a unit 18c is inserted between the units 18a and 18b and is caused to exert a wedging action against both of the latter, the unit 18c being drawn inwardly in assembling the parts by means of a nut 22 upon a bolt 23, the head of which is elongated to fit a corresponding opening.

in the unit 18, the nut 22 bearing upon the exterior surface of the casing, whereby the unit 18C is secured to the casing. It will be apparent that the unit 18e/acts as a key to hold all of the other units in position, the units 1S being formed and arranged like the stones in a masonry arch, their contacting llOCly radial edges preventing thev movement of any unit toward the middle of the mill. Each of the units 18a, 18b and 18 is provided along one edge lwith an integral into prevent slippage but to thicken the available surface of the lining units at their edges, thus greatly assisting in the retention of the units in place by the wedging action.

The vmill is to be rotated in the direction of the arrow A, Fig. 5. It will be noted that the ribs'upon the units, as illustrated in this preferred embodiment of the invention, are located at their rear of each unit with respect to the direction of its movement as the mill turns and that the forward surface of each rib slopes down very gradually to the thickness of the unit proper, while the opposite side of the rib is abrupt in order to form a comparatively thick abutment for the edge of the next unit as above described. As the mill turns more -orless rapidly, the ribs aided by centrifugal force carry the balls or pebbles upward along the side of the mill for a short distance Vuntil gravity overcomes the tendency. It is evident that ribs having square surfaces would `carry the balls much higher and that consequently it is impracticable to run a mill having such ribs very rapidly. With our improved form of ribs this difficulty is overcome.

Two of the units' 18 are cut a'way at 4 to correspond with the door opening in thel casing and a lining piece 24 with ribs upon :its inner surface constituting continuations of the ribs upon the units which are cut away as aforesaid is fastened to the door by means of a screw bolt 25 passed through an the similar units of the 18 group With the wedging unit, we may use a bolt fastening similar to the fastenings 22, 23, but in the preferred form we omit this asunnecessary.

The lining for the portion 5 of the casing, consists of units 30 having-ribs31. No permanent fastenings, such as 22, 23, are required for this series of units either, al-

though such fastenings may be employed during the assembling of the lining as will hereinafter more fully appear.

The adjacent end edgesvof the units 18, 28 and 30 are forced into close union and are held there by wooden wedges 34. Small iron or steel wedges may also be driven into the wooden wedges if required. The wedges 34 are driven between the outer extremities ofy the units 18 and the shoulders 17 of the hollowT end support 14, and between the outer extremities of the units 30 and similar shoulders upon end supports 35 which in the present instance, we have illustrated as secured in position by means of bolts 36.

The mill may be revolved in any suitable manner as by means of a gear 37 fastened by means of bolts 38 to a cone-shaped collar 39 secured to the casing 5.

Although we prefer that the ribs upon the lining units shall b e located at one edge thereof, as shown in Figs. 1 to 7 inclusive, we do not desire to be limited to this construction as other arrangements may be elnployed, such for instance, as a plurality of ribs upon each unit (see Fig. 8). However, 1n every case, we propose to form ribs with a curvedsurface upon the side which is forward as the mill turns. In Fig. 8 the units are each provided with outer ribs 40 and a middle rib 41. A greater number of ribs 41 might be employed if desired. The outer Asides of the ribs-40 may be somewhat more abrupt than the inner sides.

In assembling our improved lining, the following procedure has been found' to be advisable: irst, the two end supports 14 and 35 are put in placeas shown in the drawing. Then the key units 18c and similar units of the series 28 and 30 are bolted to the casing. Any means of temporarily5securing the key units of the series 28 and 30 may be em-- Rloyed, but bolt fastenings, such as 22, 23 have been found satisfactoryv in practice. Care must be exercised to place the key unit 18c at the proper position to cause the door opening to fall at the desired point. Next the unit 18a and similar units of the series 28 and 30 are put in position and vbelting str1ps`12 and cement 13 worked in behind them after which the wedges at each endvl are driven. This procedure is continued all l around the mill until the unit 18b and the corresponding units of the other series are reached. Before placing these latter units, the key units are removed or loosened sufiiciently to permit the l units to be slid into place. The key units of the series 30 and 28 are then'placed in the order named after which the unit 18 is bolted down. The irr- ,ner end of the unit 18c is perpendicular to greater bevel than the other units of that series in order to permit the ready placing of the unit 18C after all the other units are in position. It will be apparent that when y the assembling is complete, the temporary fastenings of the key units of the groups 28 and 30 may beremoved as these units are held by the wedging action upon their ends.

During the process of assembling, the mill is revolved so as to keep the units next to be placed a little above the level of the axis of the mill. This allows the cement to work down by gravity and the units are placed easily.

In the form of construction shown in Fig. 9, provision is made for reducing the size and consequently the weight of the individual units of the lining for the part por section 6 of the mill. For the -reason that on account of the greater length required of these units, the weight particularly in mills of large diameter will be considerable and therefore too heavy to be handled conveniently, assuming that the units are of the construction designated 18 in the other views. In this new form the lining is composed of main or full length members 46 and intermediate or auxiliary members 47. Each member 4G is composed of a body part 48 and a terminal part 49, shoulders 50 being formed at the junction of the parts 48 and 49 and extending outwardly from the I part 48 where it joins the part 49. Each auxiliary member 47 is interposed between two members 46, its smaller extremity engaging the adjacent shoulders 50 of the two main members and thus filling the space between the two members 46 beyond the shoulders 50 in the direction of the largest circumference of the mill. Hence by virtue of this construction, it becomes practicable to reduce the weight of each main lining unit used in this part of the mill to the extent of the weight of the member 47.

In Fig. l0 are illustrated in cross section several different modifications of units all hollowed out upon their outer surfaces opposite the rib or ribs upon the inner surfaces whereby the thickness of each unit is made practically constant and therefore as strong in o'ne place as in another and yet making itpossible to lessen the weight of the lining, a feature of great importance in large mills .where the different units are necessarily heavy.

In the construction disclosed in Fig. 11,

the units 46a and 46b have their adjacent edges beveled off inwardly and away from each other as shown at 3 and 4. After the units havev been set in position, a unit 46c is inserted between the'units 46a and 46b and is caused to exert a wedging action against both of the latter, the unit 46c being drawn inwardly in assemblinggthe parts inthe same manner as the unit 18C, and by employing similar means. l

We claim as our invention:

1. In a ball or pebble mill, a casing symmetrically arranged with respect to all planes passing through its axis and a lining of hard material composed of units held in place by wedging action, each of said units having integral therewith an inwardly eX- tending rib arranged longitudinally of the mill, the side edges of said units ,being formed to lie in planes through the axis of rib being located with one side co-incident with one of the side edges of its unit and the other side of the rib sloping gradually to the surface of the unit, and means inserted between two of saidunits for retaining the units in close engagementwith each other, said last named means being secured to the casing.

2. In al ball or pebble mill," a casing having a cone-shaped portion, a lining for said portion consisting of a series of units extending from the base'of the cone to a point near its apex, said units at their base portions being cut away uponA each side, and further units placed between the first named units at their cut away portions, the side edges of both series of units lying in planes extending through the axis of the cone whereby they have a wedging action upon each other.

3. In a ball or pebble mill, a casing having a cone shaped portion, a llining for said portion, consisting of a series of concavoconvex uhits resembling in shape two arrow heads placedpoint to. butt, said units extending from the base of the cone to a point near its apex, and further units shaped like. single arrow heads/and placed between the base portions of the first named units, the side edges of both series `of units lying in planes extending through the axis of the cone whereby they have a wedging action upon each other.

4. In a ball or pebble mill, a casing having a cone shaped portion, a lining for said portion consisting of a series of units extending from the base of the cone to a point near its apex, said units at their base portions being cut away at each side, and further units placed between the rst named units at their cut-away portions, substantially as described.

5. In a ball or pebble mill, a casing having a cone shaped portion, a lining for said portion consisting of a series ofI concavo convex units resembling in shape two arrow heads-placed pointto butt, said units extending from the base of the cone to a point near its apex, and further units shaped like single arrow heads, and placed between the base portions of the first named units.

6. In a ball or pebble mill, a'casing having a cone shaped portion, a lining for said `portion consisting of a 'series 4ofunits exthe mill when the units are assembled, each -tending .from the base'of the cone to a point near its apex, said units at their base portions being eut away upon each side, and further units placed between the irst named v units at their cut away*portions, theside edges of both series of units lying 1n planes -ex-A tending through the axis of the cone, Whereby they have a wedging action upon each other, and means inserted between two of said units for retaining?,` Ithe units in close engagement with each other.

7. In a ball or pebble mill, a casing having a cone shaped portion, a lining for said portion, consisting of a series of cancavoconvex units resembling in shape two arrow heads placed point to butt, said units extending from the base ofthe cone to a point near engagement with each other, said last named' means being secured to the casing.

In testimony whereof we aiix our signatures in presence of two witnesses.

HANS A. HANSEN. p JOSEPH M. SCHMUESER. Witnesses:

W. S. HoGG, H. L. HOLT. 

